Greg Colbrunn, the Boston Red Sox hitting coach who had a serious health scare earlier this season, has chosen not to return for the 2015 season.

Colbrunn has cited a desire to spend more time with his family -- he has two teenage daughters -- as a reason he'd elect not to return next season.

Boston went from having the majors' most prolific offense in 2013 -- Colbrunn's first season as a big league hitting coach -- to having one of the worst in 2014. The Red Sox finished tied for 12th in runs scored with 634. They were 14th in slugging percentage (.369), 12th in home runs (123), eighth in on-base percentage (.316) and 14th in OPS+ (92), which is on-base plus slugging adjusted to a team's home park.

The Red Sox were last in the league in batting average on the road (.233) and last in batting average with runners in scoring position (.237).

On June 4 in Cleveland, Colbrunn, 45, was rushed from the ballpark to the Cleveland Clinic after developing bleeding on the brain, a potentially life-threatening condition. He returned to the team on a full-time basis six weeks later.

The Red Sox had added an assistant hitting coach, Victor Rodriguez, before the 2013 season. It's unclear whether Rodriguez will be promoted.